Toolholder



-' C. E. RUNDORFF TOOLHOLDER June 13, 1950 Filed Feb 10, 1947 INVENTOR. CHARLES E.RUNDORFF ATTORNEYS Patented June 13, 1950 'TOOLHOLDER Charles E. Rundorff, Detroit, Mich., assignor to National Twist Drill & Tool Company, Rochester, Mich., a corporation of Michigan Application February 10, 1947, Serial No. 727,609

6 Claims.

The invention relates to tool holders of that type in which there is a torque transmitting engagement between the same and the tool held thereby and which are adapted to hold the tool in coaxial relation to a relatively rotatable work holder.

It is the object of the invention to obtain a, construction of this type in which the tool may be quickly engaged with or disengaged .from the holder and locked when engaged in accurately centered alignment with the spindle. To this end the invention consists in the construction as hereinafter set forth.

In the drawings:

Fig. 1 is a central, longitudinal section through my improved rotary tool holder showing the tool in engagement therewith;

Fig. 2 is a cross-section on line 2-2, Fig. 1, showing the manner of engaging the tool with the holder;

Fig. 3 is a similar view showing the tool locked to the holder; and

Fig. 4 is a section on line 4-4, Fig. 1.

As illustrated A is a member for directly engaging the rotary spindle or arbor and which is provided with a tapering shank B for engagement with a corresponding socket, having at its inner end an internally threaded recess C for engagement with securing means. At the outer end of the shank B is a radially outwardly extending flange D, having notches D therein forming driving slots for engaging the spindle of the machine. Projecting outward beyond the portion D is a portion E which is externally threaded at F and has projecting beyond'the same a cylindrical portion G of smaller diameter. H is a tapering tool receiving socket, having its entrance end in the portion E which portion at its outer end has therein diametrically opposite notches I. The tool J such, for instance, as an end mill is provided with a tapering shank K for fitting the socket H and with a cross pin L in and projecting beyond said shank for engagement with the notches .I to form a torque transmitting connection. The tool is further provided with an annular shoulder M projecting radially outward beyond'the tapered shank for use in extracting the tool from its socket, as will be hereinafter described.

To provide means for quickly engaging and locking the tool in its socket and for alternative- 1y disengaging it from its socket, I have provided the following construction. N is asleeve member fitting over the cylindrical portionGof the projection E. The outer end of this sleeve has a radially inwardly extending flange O, which is partly cut away. As specifically shown in Fig. 2, the flange has diametrically opposite quadrants O and is cut away in the intermediate quadrants 0 The quadrants O extend inward so as to overlap the projecting portions oi the pin L and also the shoulder M. However, the latter is on the outer side of the flange and is not normally in contact therewith, but the pin L is on the inside of the quadrants O and is entered into engagement therewith'through the cutaway quadrants 0 On its external surface the sleeve N is provided with a threaded portion N. The threads of which differ from those of the threaded portion F and-are of larger diameter. Preferably, the threaded portions F and N are the one right-hand and the other left-hand. Q is acollar which has the internally threaded portions Q and Q respectively, corresponding to the threaded portions F and NC Thus rotation of the collar Q in one direction will draw the sleeve N inward on the cylindrical portion G, while rotation in the opposite direction will force it outward thereon. In its inward movement the quadrants O engaging the pin L will force the tapered shank K into the socket H and firmly lock it in this position. Qn the other hand, the rotation of the collar Q in the opposite direction will engage the quadrants O with the shoulder M and force the tool outward withdrawing the tapered shank from the socket. To limit rotation of the sleeve N with the coilar Q through frictional engagement therewith, 1' preferably employ a stop .pin P which projects from the member LE inone of the-cut-out quadrants 0 so as to be in the path of the quadrants O. This will permit a limited rotation of the sleeve N with respect to the portion Eso that after the pin L has been passed through the cutaway quadrants O and-engaged with the notches I, the sleeve may be revolved to register the quadrants 0' with said pin.

With the construction as above described, the tool holder may be mounted on either a rotatable or stationary spindle (not shown) to be held in alignment with a relatively rotatable work holder. The tool is engaged with the holder by first registering the cut away quadrants O with the notches I, then inserting the tapered shank K into the socket H, rotating the sleeve N to register'the quadrants O with the pin L on the outer side thereof and, finally, by rotating the collar Q in a direction which will cause the right and left-hand threads to draw the sleeve inward. The tool may be removed at any time by the reverse rotation of the collar Q, which by-engaging the quadrants 0' with the annular shoulder M will force the shank K outward from its socket and will disengage the pin L from the notches I.

What I claim as my invention is:

l. A tool holder comprising a member having a shank for engagement with a spindle or arbor and an outwardly projecting portion provided with a tapering tool receiving socket, said outwardly projecting portion having externally a threaded portion and a cylindrical portion of smaller diameter notched at its outer end, a sleeve engaging said cylindrical portion having a radially inwardly extending flange at its outer end partially cut away, said sleeve having an externally threaded portion adjacent to the aforesaid threaded portion but of larger diameter and differential with respect thereto, a tool having a tapering shank for engaging said tapering socket, also having a pin projecting from said tapering shank to overlap said flange and to engage said notched end portion to form a torque transmitting means and an annular shoulder projecting radially outward beyond said tapering shank, and a collar having internally threaded portions corresponding respectively to the externally threaded portions on said projection and sleeve whereby the rotation of said collar in one direction will contact said flange with said pin and draw said tapered shank into firm engagement with said socket and rotation in the opposite direction will engage said shoulder and force said tapering shank out from said socket.

2. A tool holder comprising a member having a shank for engagement with a spindle or arbor and an outwardly projecting portion provided with a tapering tool receiving socket, said outwardly projecting portion having externally a threaded portion and a cylindrical portion of smaller diameter notched at its outer end, a sleeve engaging said cylindrical portion having a radially inwardly extending flange at its outer end partially cut away, said sleeve having an externally threaded portion adjacent to the aforesaid threaded portion but difierent therefrom, a tool having a tapering shank for engaging said tapering socket, also having a pin projecting from said tapering shank to overlap said flange and to engage said notched end portion to form a torque transmitting means and an annular shoulder projecting radially outward beyond said tapering shank, and a collar having internally threaded portions corresponding respectively to the external threaded portions on said projection and sleeve whereby the rotation of said collar in one direction will contact said flange with said pin and draw said tapered shank into firm engagement with said socket while rotation in the opposite direction will engage said flange with said annular shoulder and force said tapering shank out of said socket.

3. A tool holder comprising a member having a shank for engagement with a spindle or arbor and an outwardly projecting portion provided with a tapering tool receiving socket, said outwardly projecting portion having externally a threaded portion and a cylindrical portion of smaller diameter notched at its outer end, a sleeve engaging said cylindrical portion having a radially inwardly extending flange at its outer end partially cut away, said sleeve having an externally threaded portion adjacent to the aforesaid threaded portion but of different hand, a tool having a tapering shank for engaging said tapering socket, also having a pin projecting from said tapering shank to overlap said flange and to engage said notched end portion to form a torque transmitting means, and a collar having internally threaded portions corresponding respectively to the external threaded portions on said projection and sleeve whereby the rotation of said collar in one direction will contact said flange with said pin and draw said tapered shank into firm engagement with said socket while rotation in the opposite direction will engage said flange with said annular shoulder and force said tapering shank out of said socket.

4. A tool holder comprising a member having a shank for engagement with a spindle or arbor and an outwardly projecting portion provided with a tapering tool receiving socket, said outwardly projecting portion having externally a threaded portion and a cylindrical portion of smaller diameter having diametrically opposite notches at its outer end, a sleeve engaging said cylindrical portion having a radially inwardly extending flange at its outer end cut away in diametrically opposite quadrants, said sleeve having an externally threaded portion adjacent to the aforesaid threaded portion but of different hand, a tool having a tapering shank for engaging said tapering socket, also having a pin extending through and projecting from said tapering shank at its opposite ends to engage said notches to form a torque transmitting means and to overlap said flange, a collar having internally threaded portions corresponding respectively to the external threaded portions on said projection and sleeve whereby said tapering shank may be engaged with said socket by passing the projecting ends of said pin through said cutaway quadrants, and may be tightened by registering the uncut flange with said pin and rotating said collar in one direction, while rotation in the opposite direction will engage said flange with said annular shoulder and force said tapering shank out of said socket.

5. A tool holder comprising a member having a shank for engaging with a spindle or arbor and an outwardly projecting portion provided with a tapering tool receiving socket, said outwardly projecting portion having externally a threaded portion and a cylindrical portion of smaller diameter having diametrically opposite notches at its outer end, a sleeve engaging said cylindrical portion having a radially inwardly extending flange at its outer end cutaway in diametrically opposite quadrants, said sleeve having an externally threaded portion adjacent to the aforesaid threaded portion but of a different hand, a tool having a tapering shank for engaging said tapering socket, also having a pin extending through and projecting from said tapering shank at its opposite ends to engage said notches to form a torque-transmitting means and to overlap said flange, a collar having internally threaded portions corresponding respectively to the external threaded portions on said projection and sleeve whereby said tapering shank may be engaged with said socket by passing the projecting ends of said pin through said cutaway quadrants and may be tightened by registering the uncut flange with said pin, and rotating said collar in one direction while rotation in the opposite direction will engage said flange with said annular shoulder and force said tapering shank out of said socket, and a stop pin projecting from said cylindrical portion into one of the cutaway quadrants to limit rotary movement of said sleeve by friction of said collar during rotation of the latter. 1

6. A tool holder comprising a member engageable with a spindle or arbor provided at its outer end with a tapering tool receiving socket with notches on diametrically opposite sides of the wall of said socket, a tool having a tapering shank for engaging said tapering socket also having a cross-pin for engaging said notches and a radially projecting annular shoulder outward beyond said pin, and means for drawing said tapering shank into said socket and alternatively forcing it out of the socket comprising a sleeve externally engaging the wall of said socket provided with an inwardly extending flange cutaway for the passage of said pin therethrough to arrange said flange between said pin and annular shoulder, said sleeve being rotatable to overlap said pin by said flange and a collar having a differential threaded engagement with said sleeve and with REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,578,311 Grosset Mar. 30, 1926 1,760,354 Gartin May 27, 1930 2,469,014 Stalhandske May 3, 1949 

